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1.
Sci Total Environ ; 917: 170438, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38286283

RESUMO

Uncertainty in methane (CH4) exchanges across wetlands and grasslands in the Qinghai-Tibetan Plateau (QTP) is projected to increase due to continuous permafrost degradation and asymmetrical seasonal warming. Temperature plays a vital role in regulating CH4 exchange, yet the seasonal patterns of temperature dependencies for CH4 fluxes over the wetlands and grasslands on the QTP remain poorly understood. Here, we demonstrated a stronger warming response of CH4 exchanges during the non-growing season compared to the growing season on the QTP. Analyzing 9745 daily observations and employing four methods -regression fitting of temperature-CH4 flux, temperature dependence calculations, field-based and model-based control experiments-we found that warming intensified CH4 emissions in wetlands and uptakes in grasslands. Specifically, the average reaction intensity in the non-growing season surpasses that in the growing season by 1.89 and 4.80 times, respectively. This stronger warming response of CH4 exchanges during the non-growing season significantly increases the regional CH4 exchange on the QTP. Our research reveals that CH4 exchanges in the QTP have a higher warming sensitivity in non-growing seasons, which meanwhile are dominated by a larger warming rate than the annual average. The combined effects of these two factors will significantly alter the CH4 source/sink on the QTP. Neglecting these impacts would lead to inaccurate estimations of CH4 source/sink over the QTP under climate warming.

2.
World J Clin Cases ; 11(28): 6707-6714, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37901008

RESUMO

BACKGROUND: Childhood asthma is a common respiratory ailment that significantly affects preschool children. Effective asthma management in this population is particularly challenging due to limited communication skills in children and the necessity for consistent involvement of a caregiver. With the rise of digital healthcare and the need for innovative interventions, Internet-based models can potentially offer relatively more efficient and patient-tailored care, especially in children. AIM: To explore the impact of an intelligent Internet care model based on the child respiratory and asthma control test (TRACK) on asthma management in preschool children. METHODS: The study group comprised preschoolers, aged 5 years or younger, that visited the hospital's pediatric outpatient and emergency departments between January 2021 and January 2022. Total of 200 children were evenly and randomly divided into the observation and control groups. The control group received standard treatment in accordance with the 2016 Guidelines for Pediatric Bronchial Asthma and the Global Initiative on Asthma. In addition to above treatment, the observation group was introduced to an intelligent internet nursing model, emphasizing the TRACK scale. Key measures monitored over a six-month period included the frequency of asthma attack, emergency visits, pulmonary function parameters (FEV1, FEV1/FVC, and PEF), monthly TRACK scores, and the SF-12 quality of life assessment. Post-intervention asthma control rates were assessed at six-month follow-up. RESULTS: The observation group had fewer asthma attacks and emergency room visits than the control group (P < 0.05). After six months of treatment, the children in both groups had higher FEV1, FEV1/FVC, and PEF (P < 0.05). Statistically significant differences were observed between the two groups (P < 0.05). For six months, children in the observation group had a higher monthly TRACK score than those in the control group (P < 0.05). The PCS and MCSSF-12 quality of life scores were relatively higher than those before the nursing period (P < 0.05). Furthermore, the groups showed statistically significant differences (P < 0.05). The asthma control rate was higher in the observation group than in the control group (P < 0.05). CONCLUSION: TRACK based Intelligent Internet nursing model may reduce asthma attacks and emergency visits in asthmatic children, improve lung function, quality of life, and the TRACK score and asthma control rate. The effect of nursing was significant, allowing for development of an asthma management model.

3.
medRxiv ; 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37873362

RESUMO

Influenza viruses continually evolve new antigenic variants, through mutations in epitopes of their major surface proteins, hemagglutinin (HA) and neuraminidase (NA). Antigenic drift potentiates the reinfection of previously infected individuals, but the contribution of this process to variability in annual epidemics is not well understood. Here we link influenza A(H3N2) virus evolution to regional epidemic dynamics in the United States during 1997-2019. We integrate phenotypic measures of HA antigenic drift and sequence-based measures of HA and NA fitness to infer antigenic and genetic distances between viruses circulating in successive seasons. We estimate the magnitude, severity, timing, transmission rate, age-specific patterns, and subtype dominance of each regional outbreak and find that genetic distance based on broad sets of epitope sites is the strongest evolutionary predictor of A(H3N2) virus epidemiology. Increased HA and NA epitope distance between seasons correlates with larger, more intense epidemics, higher transmission, greater A(H3N2) subtype dominance, and a greater proportion of cases in adults relative to children, consistent with increased population susceptibility. Based on random forest models, A(H1N1) incidence impacts A(H3N2) epidemics to a greater extent than viral evolution, suggesting that subtype interference is a major driver of influenza A virus infection dynamics, presumably via heterosubtypic cross-immunity.

4.
Environ Pollut ; 335: 122322, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37544405

RESUMO

Flutolanil has been detected worldwide in aquatic environment and fish, which has become an undeniable stressor on ecosystem and human health. Flutolanil has been reported to be toxic to aquatic organisms. However, the pathophysiological and molecular mechanism behind the detrimental effects remains obscure. Here we reported hepatotoxicity induced by flutolanil in HepG2 cells and zebrafish, as revealed by toxicokinetic, HE staining, miRNAs-mRNAs sequencing, molecular dynamic simulations and dual luciferase reporter assays. Collectively, our results indicated that flutolanil could be absorbed by and accumulated in the liver of zebrafish, causing hepatic vacuolar degeneration, steatosis and nuclear condensation and abnormal liver function, where its exposure at environmental levels disrupted the expressions of miRNA-26a-5p and its target gene socs1a by mediating JAK-STAT signaling pathway, which was partially responsible for hepatotoxicity, correlated with oxidative stress, cell apoptosis, inflammation, cell cycle disorder and mitochondrial dysfunction. These findings suggest that miRNA-26a-5p/socs1a can serve as potential biomarkers of hepatotoxicity in zebrafish following exposure to flutolanil. This uncovered route will provide a new tool for the risk assessment of flutolanil and a guide to proper use of flutolanil and environmental remedy, and open up a new horizon for liver disease assessment.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , MicroRNAs , Animais , Humanos , Peixe-Zebra/metabolismo , MicroRNAs/genética , Ecossistema , Doença Hepática Induzida por Substâncias e Drogas/genética
5.
Sci Total Environ ; 892: 164736, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37295516

RESUMO

Amplification of hydrological cycle under warming climate is anticipated to result in intensified precipitation characterized by fewer, more intense events and correspondingly longer dry intervals between events, even without major changes in annual total precipitation. Vegetation gross primary production (GPP) in drylands is highly responsive to intensified precipitation, however, how intensified precipitation influences GPP in global drylands is not well understood. Based on multiple satellite datasets from 2001 to 2020 and in-situ measurements, we investigated the effects of intensified precipitation on global drylands GPP under diverse annual total precipitation along the bioclimate gradient. Dry, normal, and wet years were identified as years with annual precipitation anomalies below, within, and above the range of one standard deviation. Intensified precipitation led to increases or decreases of GPP during dry or normal years, respectively. However, such effects were largely weakened during wet years. The responses of GPP to intensified precipitation were mirrored by soil water availability, as intensified precipitation enhanced root zone soil moisture, and thus vegetation transpiration and precipitation use efficiency during dry years. During wet years, root zone soil moisture showed less response to changed precipitation intensity. Land cover types and soil texture regulated the magnitude of the effects along the bioclimate gradient. Under intensified precipitation, shrubland and grassland distributed in drier region with coarse soil texture showed greater increases of GPP during dry years. As global precipitation will likely further intensify, the impacts of intensified precipitation on dryland carbon uptake capacity will be highly diverse along the bioclimate gradients.


Assuntos
Clima , Solo , Mudança Climática , Ecossistema
6.
Biotechnol Genet Eng Rev ; : 1-22, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37018456

RESUMO

In the treatment of lumbar burst fractures with nerve injury, fusion is often required to rebuild spinal stability, but it can lead to the loss of motor units and increase the occurrence of adjacent segment diseases. Thus, a novel approach of lumbar canal decompression with "pedicle-plasty" strategy (DDP) was needed in clincal treatment. Firstly, image measurement analysis, the images of 60 patients with lumbar spine CT examinations were selected to measure osteotomy angle (OA), distance from the intersection of osteotomy plane and skin to the posterior midline (DM),transverse length of the osteotomy plane (TLOP), and sagittal diameter of the outer edge of superior articular process (SD). Secondary, cadaver study, distance between the intermuscular space and midline (DMSM), anterior and posterior diameters of the decompression (APDD), and lateral traction distance of the lumbosacral plexus (TDLP) were measured on 10 cadaveric specimens. Finally, procedure of DDP was demonstrated on cadaver specimens. OA ranged from 27.68°+4.59° to 38.34°+5.97°, DM ranged from 43.44+6.29 to 68.33+12.06 mm, TLOP ranged from 16.84+2.19 to 19.64+2.36 mm, and SD ranged from 22.49+1.74 to 25.53+2.21 mm. DMSM ranged from 45.53+5.73 to 65.46+6.43 mm. APDD were between 10.51+3.59 and 12.12+4.54 mm, and TDLP were between 3.28+0.81 and 6.27+0.62 mm.DDP was successfully performed on cadaveric specimens. DDP, as a novel approach of decompression of burst fractures with pedicle rupture, can fully relieve the occupation and at the same time preserve the spinal motor unit because of no resection of intervertebral discs and no destruction of facet joints,and has certain developmental significance.

7.
Int J Mol Sci ; 23(24)2022 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-36555781

RESUMO

BACKGROUND: Thrombocytopenia has long been considered an important complication of chemotherapy and radiotherapy, which severely limits the effectiveness of cancer treatment and the overall survival of patients. However, clinical treatment options are extremely limited so far. Ruxolitinib is a potential candidate. METHODS: The impact of ruxolitinib on the differentiation and maturation of K562 and Meg-01 cells megakaryocytes (MKs) was examined by flow cytometry, Giemsa and Phalloidin staining. A mouse model of radiation-injured thrombocytopenia (RIT) was employed to evaluate the action of ruxolitinib on thrombocytopoiesis. Network pharmacology, molecular docking, drug affinity responsive target stability assay (DARTS), RNA sequencing, protein blotting and immunofluorescence analysis were applied to explore the targets and mechanisms of action of ruxolitinib. RESULTS: Ruxolitinib can stimulate MK differentiation and maturation in a dose-dependent manner and accelerates recovery of MKs and thrombocytopoiesis in RIT mice. Biological targeting analysis showed that ruxolitinib binds directly to Toll Like Receptor 2 (TLR2) to activate Rac1/cdc42/JNK, and this action was shown to be blocked by C29, a specific inhibitor of TLR2. CONCLUSIONS: Ruxolitinib was first identified to facilitate MK differentiation and thrombocytopoiesis, which may alleviate RIT. The potential mechanism of ruxolitinib was to promote MK differentiation via activating the Rac1/cdc42/JNK pathway through binding to TLR2.


Assuntos
Sistema de Sinalização das MAP Quinases , Trombocitopenia , Animais , Camundongos , Trombopoese , Receptor 2 Toll-Like/metabolismo , Simulação de Acoplamento Molecular , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo
8.
ACS Omega ; 7(48): 44338-44345, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36506192

RESUMO

Water quality guarantee in remote areas necessitates the development of portable, sensitive, fast, cost-effective, and easy-to-use water quality detection methods. The current work reports on a microfluidic paper-based analytical device (µPAD) integrated with a smartphone app for the simultaneous detection of cross-type water quality parameters including pH, Cu(II), Ni(II), Fe(III), and nitrite. The shapes, baking time, amount, and ratios of reaction reagent mixtures of wax µPAD were optimized to improve the color uniformity and intensity effectively. An easy-to-use smartphone app was established for recording, analyzing, and directly reading the colorimetric signals and target concentrations on µPAD. The results showed that under the optimum conditions, the current analytical platform has reached the detection limits of 0.4, 1.9, 2.9, and 1.1 ppm for nitrite, Cu(II), Ni(II), and Fe(III), respectively, and the liner ranges are 2.3-90 ppm (nitrite), 3.8-400 ppm (Cu(II)), 2.9-1000 ppm (Ni(II)), 2.8-500 ppm (Fe(III)), and 5-9 (pH). The proposed portable smartphone-app integrated µPAD detection system was successfully applied to real industrial wastewater and river water quality monitoring. The proposed method has great potential for field water quality detection.

9.
Int J Mol Sci ; 23(22)2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36430539

RESUMO

BACKGROUND: Cibotii rhizoma (CR) is a famous traditional Chinese medicine (TCM) used to treat bleeding, rheumatism, lumbago, etc. However, its therapeutic effects and mechanism against thrombocytopenia are still unknown so far. In the study, we investigated the effects of aqueous extracts of Cibotii rhizoma (AECRs) against thrombocytopenia and its molecular mechanism. METHODS: Giemsa staining, phalloidin staining, and flow cytometry were performed to measure the effect of AECRs on the megakaryocyte differentiation in K562 and Meg-01 cells. A radiation-induced thrombocytopenia mouse model was constructed to assess the therapeutic actions of AECRs on thrombocytopenia. Network pharmacology and experimental verification were carried out to clarify its mechanism against thrombocytopenia. RESULTS: AECRs promoted megakaryocyte differentiation in K562 and Meg-01 cells and accelerated platelet recovery and megakaryopoiesis with no systemic toxicity in radiation-induced thrombocytopenia mice. The PI3K/AKT, MEK/ERK, and JAK2/STAT3 signaling pathways contributed to AECR-induced megakaryocyte differentiation. The suppression of the above signaling pathways by their inhibitors blocked AERC-induced megakaryocyte differentiation. CONCLUSIONS: AECRs can promote megakaryopoiesis and thrombopoiesis through activating PI3K/AKT, MEK/ERK, and JAK2/STAT3 signaling pathways, which has the potential to treat radiation-induced thrombocytopenia in the clinic.


Assuntos
Trombocitopenia , Trombopoese , Camundongos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo
10.
Sci Adv ; 8(44): eabo0119, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36322652

RESUMO

Climate change is pushing temperatures beyond the thermal tolerance of many species. Whether protected areas (PAs) can serve as climate change refugia for biodiversity has not yet been explored. We find that PAs of natural (seminatural) vegetation effectively cool the land surface temperature, particularly the daily maximum temperature in the tropics, and reduce diurnal and seasonal temperature ranges in boreal and temperate regions, as compared to nonprotected areas that are often disturbed or converted to various land uses. Moreover, protected forests slow the rate of warming more at higher latitudes. The warming rate in protected boreal forests is up to 20% lower than in their surroundings, which is particularly important for species in the boreal where warming is more pronounced. The fact that nonprotected areas with the same type of vegetation as PAs show reduced warming buffer capacity highlights the importance of conservation to stabilize the local climate and safeguard biodiversity.

11.
Artigo em Inglês | MEDLINE | ID: mdl-36301113

RESUMO

With the rapid development of triboelectric nanogenerators (TENGs) for flexible wearable devices and electronic skins, challenges have gradually emerged related to the electrification surface, such as pollutant contamination and sophisticated surface adaptability. Hence, we report a simple spraying method to produce a shape-adaptive photocatalytic (SAP) triboelectric material with both self-cleaning and shape-adaptive functions. By spraying the polyvinyl alcohol solution with TiO2 photocatalysts and pre-drying cyclic, the SAP film can be adapted to a varied and intricate substrate. The highest transferred charge density of the SAP film reaches 197.5 µC/m2, when it contacts with the PTFE film. At the same time, it can degrade 74.4% of simulated pollutants under sunlight illumination, and 97% of the transferred charge density can be maintained after the degradation process, indicating good self-cleaning function and stable electrical output. Moreover, the spraying method of this allows it to have shape-adaptive functions. Accordingly, the SAP film can be deposited on the rectangular pyramid and hemispherical surface for fabricating TENGs with special shapes. This low-cost and simple spraying method further promotes the commercialized application of TENGs in the field of wearable devices and skin sensors.

12.
Phys Chem Chem Phys ; 24(37): 22889-22897, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36125231

RESUMO

This work studies the molecular reaction and dynamic mechanism of iodate reduction by nitrogen(III) in aqueous solution using the ab initio molecular dynamics (AIMD) method based on density functional theory (DFT). Two possible reaction pathways (without and with H+) are proposed. The thermodynamic parameters of the proposed reaction pathways are calculated. The theoretical calculation aspects of iodate reduction, including the atomic dipole moment corrected Hirshfeld population (ADCH) atomic charge values, the intrinsic reaction coordinate (IRC) curves, the calculated interaction regional indicator (IRI) isosurfaces with the corresponding sign(λ2)ρ scatter plots, electrostatic potential (ESP) analysis and molecular reaction dynamics are discussed in-depth. The results show that the reaction pathway with H+ is confirmed based on the Gibbs free energy analysis. The transition state proved that the iodate reduction with nitrous acid undergoes four steps according to oxygen-atom deprivation. The IRC curves describe the energy change of the chemical bonds of the reactant conformations in the four steps, with an energy reduction of 71.95, 69.35, 130.15, and 125.87 kJ mol-1, respectively. The ESP interpenetration diagram and IRI isosurfaces provide detailed information on the nucleophilicity and electrophilicity of the reactant conformations. By decreasing the O atom number in HIOx (x = 1, 2, 3), the maximum positive charge decreases, and the positive charge coverage area increases, thus resulting in energy reduction and consequently a more stable conformation. Molecular reaction dynamics analytical results indicated that a relatively stable status of the reactants of the four steps was achieved after around 200 fs, and that the HIO3-HNO2 reaction released the highest energy.

13.
Med Devices (Auckl) ; 15: 341-347, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36105561

RESUMO

Introduction: Simple non-invasive biomarker is urgently needed to detect the largely silent osteopenia in order to prevent osteoporosis-related fracture later in life. The accumulation of advanced glycation end products (AGEs) has been related to reduced bone density and osteoporotic fractures. Whether lens autofluorescence (LAF) based AGEs (LAF-AGEs) measurement could be used to assess the risk of osteopenia is aimed to investigate in this paper. Methods: Through routine health examination, 368 individuals under the age of 50 were enrolled. A dual-energy X-ray absorptiometry (DXA) device was used to measure bone mineral density (BMD) of the forearm and determine osteopenia. AGE levels were derived with LAF along with the other demographic and laboratory parameters. After deriving the age-adjusted AGE levels (AALs), a linear regression analysis and an ordered logistic regression analysis were applied to examine the associations between osteopenia and LAF-AGEs as well as AALs. Results: Negative correlations (Pearson r = -0.16, p < 0.001) were found between LAF-AGEs and T-scores. Higher AALs were significantly associated (p = 0.004) with escalated level of osteopenia in the ordered logistic analysis. Discussion: After reviewing the relevant studies, it is concluded that LAF-AGE is a more stable measure of long-term metabolic dysfunction than circulating AGE. LAF-AGEs are a valid, practical and non-invasive parameter for osteopenia risk evaluation. Further studies with longer follow-up will be helpful to clarify its effectiveness for osteoporosis risk assessment.

14.
Bull World Health Organ ; 100(6): 366-374, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35694628

RESUMO

Objective: To assess the stability of improvements in global respiratory virus surveillance in countries supported by the United States Centers for Disease Control and Prevention (CDC) after reductions in CDC funding and with the stress of the coronavirus disease 2019 (COVID-19) pandemic. Methods: We assessed whether national influenza surveillance systems of CDC-funded countries: (i) continued to analyse as many specimens between 2013 and 2021; (ii) participated in activities of the World Health Organization's (WHO) Global Influenza Surveillance and Response System; (iii) tested enough specimens to detect rare events or signals of unusual activity; and (iv) demonstrated stability before and during the COVID-19 pandemic. We used CDC budget records and data from the WHO Global Influenza Surveillance and Response System. Findings: While CDC reduced per-country influenza funding by about 75% over 10 years, the number of specimens tested annually remained stable (mean 2261). Reporting varied substantially by country and transmission zone. Countries funded by CDC accounted for 71% (range 61-75%) of specimens included in WHO consultations on the composition of influenza virus vaccines. In 2019, only eight of the 17 transmission zones sent enough specimens to WHO collaborating centres before the vaccine composition meeting to reliably identify antigenic variants. Conclusion: Great progress has been made in the global understanding of influenza trends and seasonality. To optimize surveillance to identify atypical influenza viruses, and to integrate molecular testing, sequencing and reporting of severe acute respiratory syndrome coronavirus 2 into existing systems, funding must continue to support these efforts.


Assuntos
COVID-19 , Vacinas contra Influenza , Influenza Humana , COVID-19/epidemiologia , COVID-19/prevenção & controle , Centers for Disease Control and Prevention, U.S. , Humanos , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Pandemias/prevenção & controle , Vigilância da População , Estados Unidos/epidemiologia
15.
Front Public Health ; 10: 870403, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35586004

RESUMO

With the rapid process of urbanization and global warming, many metropolises are vulnerable to high temperatures in summer, threatening the health of residents. However, green spaces can generate a cooling effect to mitigate the urban heat island effect in big cities. They can also help to improve the living quality and wellbeing of surrounding residents. In this paper, we utilized the radiative transfer equation algorithm, k-means clustering algorithm, big data crawling, and spatial analysis to quantify and map the spatial distribution, cooling capacity, and cooling contribution for surrounding communities of 1,157 green spaces within Beijing Fifth Ring Road, a typical metropolitan area. The findings showed that (1) the area proportion of the heat island in the study area is larger than that of the cooling island. Accounting for only about 30% area in the study area, the green spaces reduce the average land surface temperature by 1.32°C. (2) The spatial features of green space, such as area and shape complexity, have a significant influence on its cooling effect. (3) Four clusters of green spaces with specific spatial features and cooling capacity were identified. And there were differences among these clusters in green space cooling contribution for the surrounding communities. (4) The differences in green space cooling contribution also existed in different urban zones. Specifically, the middle zone performed significantly better than the inner and outer zones. (5) We furthered in finding that some green spaces with medium and high cooling contributions need to improve their cooling capacity soon, and some green spaces with low cooling contributions or no contributions have a good potential for constructing new communities in the future. Our study could help planners and government understand the current cooling condition of green spaces, to improve their cooling capacity, mitigate the urban heat island effect, and create a comfortable and healthy thermal environment in summer.


Assuntos
Temperatura Alta , Parques Recreativos , Pequim , Cidades , Temperatura Baixa
16.
Glob Chang Biol ; 28(13): 4097-4109, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35364612

RESUMO

Climate warming causes profound effects on structure and function of wetland ecosystem, thus affecting regional and global hydrological cycles and carbon budgets. However, how wetland plants respond to warming is still poorly understood. Here, we synthesized observations from 273 independent sites to explore responses of northern wetland plants to warming. Our results show that warming enhances biomass accumulation for vascular plants including shrubs and graminoids, whereas it reduces biomass accumulation for cryptogams including moss and lichen. This divergent response of vascular plants and cryptogams is particularly pronounced in the high latitudes where permafrost prevails. As warming continues, this divergent response is amplified, however, the reduction in cryptogams is more drastic. Warming leads to declined surface soil moisture and lowered water table, thereby shifting wetlands from a wet system dominated by cryptogams to a drier system with increased cover of vascular plants. Under a high-emission scenario of Shared Socioeconomic Pathways (SSP5), a 4.7-5.1°C mean global temperature rise will cause more than fivefold loss of cryptogams compared with current climate. As cryptogams are largely concentrated at northern high latitudes, where warming will likely be greater than the projected global mean, modification in wetland plant composition and major reduction in cryptogams are expected to occur even much earlier than 2100.


Assuntos
Traqueófitas , Áreas Alagadas , Biodiversidade , Mudança Climática , Ecossistema , Aquecimento Global , Plantas , Solo/química , Temperatura
17.
J Hazard Mater ; 416: 125835, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492792

RESUMO

Efficient iodine gas capture is necessitated in many industries like spent nuclear fuel off-gas treatment in view of environmental protection and resource recycling. However, the adsorption efficiency and stability of the current adsorbents are limited. In the present work, efficient and stable barbituric and thiobarbituric acid-based UiO-66-NH2 adsorbents (i.e., UiO-66-NH-B.D and UiO-66-NH-T.D, respectively) have been synthesized by post-synthetic covalent modification. Characterization approaches, including SEM-EDS, TEM, XRD, FTIR, XPS, 1H NMR, TGA and BET, are used to obtain information on the properties and adsorption mechanisms of these metal-organic framework (MOF) adsorbents. The kinetics and mechanisms involved are studied in detail. The treatment efficiency and recyclability of the adsorbents are checked and compared with the adsorbents reported in previous works. The results show that the current adsorbents are potentially suitable for efficient iodine gas capture. High maximum iodine adsorption amount by UiO-66-NH-B.D and UiO-66-NH-T.D (1.17 and 1.33 g/g) was achieved under 75 °C. These new adsorbents are thermally stable for iodine adsorption and regenerated and reused with good performance. The adsorption mechanisms were revealed based on experimental results, indicating that iodine is adsorbed by both physisorption and chemisorption.

18.
Environ Sci Technol ; 55(14): 10152-10163, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34229435

RESUMO

Methane (CH4) emissions from pan-Arctic wetlands provide a potential positive feedback to global warming. However, the differences in CH4 emissions across wetland types in these regions have not been well understood. We synthesized approximately 9000 static chamber CH4 measurements during the growing season from 83 sites across pan-Arctic regions. We highlighted spatial variations of CH4 emissions corresponding to environmental heterogeneity across wetland types. CH4 emission is the highest in fens, followed by marshes, bogs, and the lowest in swamps. This gradient is controlled by the water table, soil temperature, and dominant plant functional types and their interactions. The water table position for maximum CH4 emission is below, close to, and above the ground surface in bogs, marshes/fens, and swamps, respectively. The temperature sensitivity (Q10) of CH4 emissions varied among different wetland types, ranging from the lowest in swamps to the highest in fens. The interactive impact of temperature and the water table positions on CH4 emissions are regulated with dominant plant functional types. CH4 emissions from wetlands dominated by vascular plants rely more on species composition than that dominated by non-vascular plants. Wetlands with greater abundance of graminoids (e.g., fens) have higher CH4 emissions than tree-dominated wetlands (e.g., swamps). This synthesis emphasizes the role of wetland heterogeneity in determining the strength of CH4 emissions.


Assuntos
Gases de Efeito Estufa , Áreas Alagadas , Regiões Árticas , Dióxido de Carbono , Gases de Efeito Estufa/análise , Metano/análise , Solo
19.
Ann Palliat Med ; 10(12): 12607-12617, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35016447

RESUMO

BACKGROUND: Many studies have reported the advantages of anterior lumbar interbody fusion (ALIF), but the technique is associated with many complications involving nerve injury. This meta-analysis compared the outcome indicators associated with 2 fusion methods, namely, ALIF and posterolateral fusion (PLF). The clinical efficacy of ALIF was explored to provide evidence-based data for the determination of surgical methods for treating orthopedic spondylolisthesis. METHODS: Relevant literatures were retrieved from the CBMdisc, CNKI, PubMed, EBSCO, MEDLINE, Science Direct, and Cochrane databases. Keywords in Chinese and English included spondylolisthesis, spine, surgical treatment, ALIF, and PLF. Data including the visual analogue scale (VAS) score, the Oswestry Disability Index (ODI), time of operation, and fusion rate were collated. According to Cochrane manual, Rev Man 5.3 software was used for analysis. RESULTS: A total of 6 articles were included in this meta-analysis. There were significant differences in intraoperative blood loss [Z=3.34; mean difference (MD) =-142.54; 95% confidence interval (CI): -226.17 to -58.92; P=0.0008] and operation time (Z=5.45; MD =-54.31; 95% CI: -73.83 to -34.79; P<0.00001) between patients in the ALIF group and patients in the PLF group. Significant differences were observed in VAS score (Z=3.55; MD =-1.04; 95% CI: -1.62 to -0.47; P=0.0004) nor ODI score (Z=3.07; MD =-6.33; 95% CI: -10.37 to -2.28; P=0.002) between the ALIF group and the PLF group. Interestingly, there was a significant difference in the hospitalization time between the 2 groups (Z=2.39; MD=-1.48; 95% CI: -2.70 to -0.27; P=0.02). Bone fusion rate was no significantly different between patients in the ALIF group and patients in the PLF group [Z=0.43; odds ratio (OR) =0.42; 95% CI: 0.01 to 21.82; P=0.66]. DISCUSSION: The results of this meta-analysis confirmed that ALIF can effectively improve the degree of spondylolisthesis, provide superior structural stability, and ensure surgical efficacy.


Assuntos
Fusão Vertebral , Espondilolistese , Humanos , Vértebras Lombares/cirurgia , Espondilolistese/cirurgia , Resultado do Tratamento
20.
Glob Chang Biol ; 27(2): 376-387, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33118303

RESUMO

Warming in the Arctic has been more apparent in the non-growing season than in the typical growing season. In this context, methane (CH4 ) emissions in the non-growing season, particularly in the shoulder seasons, account for a substantial proportion of the annual budget. However, CH4 emissions in spring and autumn shoulders are often underestimated by land models and measurements due to limited data availability and unknown mechanisms. This study investigates CH4 emissions during spring thaw and autumn freeze using eddy covariance CH4 measurements from three Arctic sites with multi-year observations. We find that the shoulder seasons contribute to about a quarter (25.6 ± 2.3%, mean ± SD) of annual total CH4 emissions. Our study highlights the three to four times higher contribution of autumn freeze CH4 emission to total annual emission than that of spring thaw. Autumn freeze exhibits significantly higher CH4 flux (0.88 ± 0.03 mg m-2  hr-1 ) than spring thaw (0.48 ± 0.04 mg m-2  hr-1 ). The mean duration of autumn freeze (58.94 ± 26.39 days) is significantly longer than that of spring thaw (20.94 ± 7.79 days), which predominates the much higher cumulative CH4 emission during autumn freeze (1,212.31 ± 280.39 mg m-2  year-1 ) than that during spring thaw (307.39 ± 46.11 mg m-2  year-1 ). Near-surface soil temperatures cannot completely reflect the freeze-thaw processes in deeper soil layers and appears to have a hysteresis effect on CH4 emissions from early spring thaw to late autumn freeze. Therefore, it is necessary to consider commonalities and differences in CH4 emissions during spring thaw versus autumn freeze to accurately estimate CH4 source from tundra ecosystems for evaluating carbon-climate feedback in Arctic.


Assuntos
Ecossistema , Metano , Regiões Árticas , Estações do Ano , Solo , Tundra
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